Road-roller.



P. E. HOLT.

ROAD ROLLER.

APPLICATION FILED NOV. 3, 1909.

Patented Mar. 7, 1911.

3 SHEETS-BHEET 1.

1 I 17206 72 07 P/I 5792/16 P. E. HOLT.

ROAD ROLLER. APPLIOATION FILED NOV. 3, 1999.

Patented 1111.7, 1911.

3 SHEETS-SHEET 2.

P. E. HOLT.

ROAD ROLLER.

APPLICATION FILED NOV. 3, 1909.

fatented Mar.

3 SHEETS-SHEET 3.

mu. m wk Wd Ugly}? IELINY E. HOLT, 0F STOCKTON, CALIFORNIA.

ROAD-ROLLER.

Specification of Letters Patent.

Patented Mar. '2, 1911.

Application filed November 3, 1909. Serial No. 525,978.

To all whom it may concern:

Be it known that I, PLINY E. HOLT, a citizen of the United States, and residing at and whose post-office address is 836 West Poplar street, in the city of Stockton, county of San Joaquin, and State of California, have invented certain new and useful lm provements in Road-Rollers; and I do declarethe following to be a full, clear, and exact description of the said invention, such as will enable others skilled in the art to which it most nearly appertains to make, use, and practice the same.

This invention relates to improvements in road rollers, and more particularly to the driving mechanism thereof, and to the method of ballasting same.

The objects sought to be accomplished are to provide a road roller with traction rollers capable of being adjusted so as to always conform to the crown of the road; to so ballast the machine that the dead Weight car ried by it can be readily varied to suit the conditions of the road; and to utilize for ballast such cheap and easily obtained material as can be discarded when the machine is traveling from place to place and not performing the duty for which it is designed.

The invention consists in dividing the maln axle of the traction roller, and pivotmg the separate axles between brackets and a the main frame; and in pivoting their inner ends to a double yoke attached to the main framewhereby the horizontal axis of the traction rollers may be varied. The main frame of the machine is provided with Water ballast tanks adapted to carry water on the machine as dead weight, and enable it to perform the function of crushing down inequalities in the construction of road beds, or such other duties for which such a machine is adapted.

In the drawings: Figure 1 is a side elevation of a road roller drawn to illustrate the general features of this invention. Fig. .2 is a plan view from above of the same. Fig. 3 is an end elevation of the same partially in cross-section taken on the line 33 Fig. 2, drawn to illustrate the driving mechanism of the traction roller. Fig. 4 is a detail and side elevation, taken on the line- 44 Fig. 2, of the mechanism for throwing the driving pinion into and out of engagement with the driving gears for the forward and the reverse directions,

In detail, the construction consists of the main frame made up of the triangular frame comprising side beams 1 and 2, and the rectangular frame comprising the side beams 2 and 3, and end beams 4 and 5. These two frames are rigidly joined together to form the main frame of the machine. .A front steering roller 6 is journaled within a frame 7 which is pivoted as at 8, in a bracket 9, secured between the beams 1 and 2 at the apex of the triangular frame. The main axles 10 and 11, are pivoted on pins 12 and 13, between their respective brackets 14 and 15 which are fixed to The traction rollers 16,

the main frame. are journaled upon their respective axles. These axles are joined at their inner ends by pivot pins 17, to a double yoke 18, which is provided with a threaded stem 19, swiveled in the yoke and its threaded portion engaging a cross brace 20, fixed between the beams 1 and 2 of the main frame. A hand wheel 21, is fixed to the head of the threaded stem, whereby the horizontal plane of the axles may be varied by rotating the hand wheel aforesaid.

The front wheel is steered by means of a tiller chain 22, havin its ends attached to opposite sides of the Frame 7, and is wound around a steering drum 23, fixed on a vertical shaft 24 bracketed to the main frame. A worm gear 25, is fixed on the upper end of this shaft and enga es a worm 26, fixed on a steering column 2 1, journaled in brackets 28 and 29. and provided with a hand wheel 30, whereby the rotation of the hand wheel is communicated to the steeringroller to alter the course of the machine.

The motive mechanism consists of a motor 31, mounted on the main frame. A driving shaft 32 is coupled to the motor shaft by a universal joint 33, and is journaled in slidable box 34, guided between a cross plate 35, and an arch 36 fixed thereto. The box 34, is operated laterally by toggle joints consisting of links 37 and 38, respectively pivoted to the slidable box and the arch 36. The ends of these links-are joined on a pivot pin 39, to which vertical links 40 are attached. These latter are pivoted as'at 41. to the respective ends of a rocking beam 42. pivoted as at 43 on the said arch and provided with a handle 44-.

A driving pinion 45, is fixed on the end of the shaft 32, and is adapted to be thrown into and out of engagement with forward and reverse cars 46 and 47 respectively, fixed on a shafl; 48, journaled in boxes 49, fixed on the main frame. The motive mechanism is provided with a high and low speed gear 50 and 51 fixed together and splined on the shaft 48, whereon they .are slidable by means of a lever 52, pivoted on the main frame and engaging a groove 53, in the hub of a gear 51. The traction rollers are driven by pinions 54 and 55, engaging internal gears 56, fixed within the rim of traction rollers 16. These driving pinions are driven through a differential gear consisting of a bevel gear 57, keyed to a shaft 58 on which the pinion 54 is also keyed. The bevel gear 57, is enmeshed with a driving pinion 59, journaled on the studs fixed 'to the shell 50 of the differential gear. A bevel gear 61 is enmeshed with the pinion 59, and has a fixed engagement with the driving pinion 55, which is free on the shaft 58. Spur gears 62 and 63, are rigidly ,attached to the shell 60, and are adapted to be selectively enmeshed with their respective gears 50 and 51 on the shaft 48, controlled by the hand lever 52, whereby the ratio of speed between the motor and the traction rollers may be selectively varied. The differential gear performs its function when the machine is rounding corners.

The brake system consists of a brake band 64, externally applied to the shell 60, of the differential gear. The opposite ends of the brake band are pivoted to a hand lever 65, on o posite sides of the pivot 66 thereof, whic is fixed in a bracket 67, attached to the main frame; whereby the swing of the hand lever causes the brake band to friction ally pinch the shell of the differential gear and arrest the rotation of the traction roller 16 geared thereto. When it is desired to alter the direction of progress of the machine the hand lever 44, is thrown over the center until the driving pinion 45 engages either of the desired driving gears 46 or 47. An adjustable stop 68, limits the throw of the toggle pivot 39, to cause the proper engagement ofthe two gears. When a reversible motor is used the reversing gear described is not necessary.

Heretofore it has been the practice in the construction of road rollers to make the rollers, the frame work, and the general mechanism entering into its construction abnormally heavy in so far as their operative functions are concerned in order that the aggregate weight of the machine might be suflicient to give it the necessary crushing power. Although the functional effect of this practice was correct, it made such a machine expensive to build because the dead weight was attained with expensive material whereas in the present instance only suffiing water tanks 69 and 70, carried by the main frame. In traveling from place to place these tanks are empty. lVhen the roller is in operation they are filled to give the necessary crushing weight. This is particularly advantageous in the construction of bituminous or asphalt avements, the substrata of which shoul heavy crushing weight while the bituminous or asphalt stratum requires a much lighter treatment; heretofore this has necessitated the operation of two expensive rollers, one of light and one of heavy burden.

It is obvious that the present machine combines within itself the possible range of burden between the maximum and minimum. Other advantages are also present which need not be herein set forth.

Having thus described this invention what is claimed and desired to secure by Letters Patent is:

1. In a road roller, a main frame comprising a triangular frame and a rectangular frame resting upon and rigidly secured to said triangular frame; separate main axles mounted 'on horizontal pivots fixed on the main frame; traction rollers journaled on said axles; means for adjusting the angle of said axles and locking the same; a steering truck mounted under the main frame; and a motive and power transmitting mechanism mounted-on the main frame and engaging said traction rollers.

2. In a road roller, :1 main frame comprising a triangular frame and a rectangular frame; ballast tanks mounted on said frame; traction rollers mounted upon axles mounted on horizontal pivots on the main frame; mean for adjusting said axles on said pivots and locking the same; a steering truck pivoted under the main frame; and a motive and power transmission mechanism.

3. In a road roller, a main frame; ballast tanks mounted on said frame; traction rollers, means for adjusting the angle of said traction rollers and locking the same, and a motive power transmission mechanism for said traction rollers mounted on the main frame.

4. In a road roller a main frame, traction rollers mounted in said frame, and means for adjusting the angle of said rollers and locking them in the adjusted position.

5. In a road roller, a main frame comprising a combined triangular and rectangular frame; traction rollers mounted upon axles pivoted upon horizontal pivots in the main frame; and means for adjusting and locking said axles.'

6. In a road roller a main frame, traction be rolled under arollers, pivotally supported axles for said rollers, and means for adjusting and locking said axles.

7. In a road roller a main frame, traction rollers, pivotally supported axles for said rollers, and an adjusting member pivotally connected to said axles.

8. In a road roller a main frame, traction rollers, pivotally supported axles for said rollers, a yoke axles, and an ad ust-ing screw engaging said yoke.

In testimony whereof, I have hereunto set my hand.

PLINY E. HOLT.

Witnesses:

BALDWIN VALE, P. S. SPRINGER.

ivotally connected to said 10 I 

